v21.1 Overworld Weather Enhancements 2.0

This is a rerelease of my old script tutorial for Weather Sound Effects. It was pointed out to me that I hadn't posted updates to it here since 17.1. So, I took the initiative to update it to v21.1 and also make it a plugin (with some enhancements made by @http404error). Installation is easy, just open the .rar file and drop both folders into your root directory.